The present invention relates to methods for producing controlled release ingredients for use in chewing gum.
In recent years, effort has been devoted to controlling the release characteristics of various ingredients in chewing gum. Most notably, attempts have been made to delay the release of sweeteners and flavors in various chewing gum formulations to thereby lengthen the satisfactory chewing time of the gum. Delaying the release of sweeteners and flavors can also avoid an undesirable overpowering burst of sweetness or flavor during the initial chewing period. On the other hand, some ingredients have been treated so as to increase their rate of release in chewing gum. In addition, other efforts have been directed at delaying or preventing altogether the release of active ingredients in the chewing gum formulation during storage of the gum, to thereby increase the stability of the ingredient over time.
For example, U.S. Pat. No. 4,597,970 to Sharma et al., teaches a process for producing an agglomerated sweetener wherein the sweetener is dispersed in a hydrophobic matrix consisting essentially of lecithin, a glyceride, and a fatty acid or wax having a melting point between 25.degree. and 100.degree. C. The method disclosed uses a spray congealing step to form the sweetenercontaining matrix into droplets followed by a fluid bed second coating on the agglomerated particles.
U.S. Pat. Nos. 4,515,769 and 4,386,106, both to Merrit et al., teach a two step process for preparing a delayed release flavorant for chewing gum. In this process, the flavorant is prepared in an emulsion with a hydrophyllic matrix. The emulsion is dried and ground and the particles are then coated with a water impermeable substance.
U.S. Pat. No. 4,230,687, to Sair et al., teaches a process for encasing an active ingredient to achieve gradual release of the ingredient in a product such as chewing gum. The method described involves adding the ingredient to an encapsulating material in the form of a viscous paste. High shear mixing is used to achieve a homogeneous dispersion of the ingredient within the matrix which is subsequently dried and ground.
U.S. Pat. No. 4,139,639, tc Bahoshy et al., teaches a process of "fixing" aspartame by co-drying (by spray or fluid bed drying) a solution containing aspartame and an encapsulating agent, such as gum arabic, to thereby surround and protect the aspartame during storage in the gum.
U.S. Pat. No. 4,384,004, to Cea et al., teaches a method of encapsulating aspartame with various solutions of encapsulating agents using various encapsulation techniques such as spray drying in order to increase the shelf-stability of the aspartame.
Naturally, the processes which use spray drying or fluid bed techniques for encapsulating the ingredients involve a relatively large investment in equipment and require skilled operating personnel and sophisticated process controls.